I'm not at your level or conditioning but when I was on D I was a more offensive minded guy and had similar struggles. If my forwards weren't moving and getting open obviously it caused problems.

I have to agree 100% with the advice above, that's what I did. I started pushing deeper into the O zone which got me more involved in the play and kept pressure up. I also started carrying the puck more and shortened up my stick to do that. I'm back at forward now but those things helped when I was stuck in mid-season ruts.

Oddly enough the general advice for slumps is to "keep it simple, focus on positioning, etc" but for me it was the opposite, I needed to get the puck as much as possible and play more aggressive.